25 : 9
Samples · Sprocket Designer
28 chain drives, ready to open
BMX, road and mountain bike, motorcycle and industrial roller-chain drives. Each opens in the Sprocket Designer with both sprockets and the chain around them, in 3D, every setting in place and ready to change. Every sprocket's stress was checked in the app; its card says the peak stress and safety factor. Looking for pulleys or gears? See the timing pulley samples and the gear samples.
Use
25 : 9
25/9 · classic five-spoke
BMX street 25/9
The straight five-spoke street sprocket, after BSD's Guard.
25 : 9
28 : 9
28/9 · six tapered spokes
BMX street 28/9
Six spokes tapering from 16 mm at the hub to 13 mm at the rim, 12° offset.
28 : 9
28/9 · overlapping Y star
BMX street 28/9
Six Y spokes forking into a star lattice, like Wethepeople's Turmoil. On a 25T the forks leave too little room to pass the strength check, so the star is a 28T.
44 : 16
44/16 · windowed race ring
BMX race 44/16
Five-bolt 110 BCD ring with windows between the bolts, on a 16T freewheel cog.
43 : 16
50 : 15
50 × 15 · compact big ring
Road 50/34 · 11-28, big ring
Bolt tabs on Shimano's 110 × 4, in a cruising gear.
34 : 28
34 × 28 · compact lowest gear
Road 50/34 · 11-28, lowest gear
The inner ring on the 11-28's biggest cog.
52 : 15
36 : 34
36 × 34 · mid-compact lowest gear
Road 52/36 · 11-34, lowest gear
The inner ring on an 11-34's 34T cog, six tapered spokes at a 12° offset.
53 : 15
39 : 25
39 × 25 · classic lowest gear
Road 53/39 · 11-25, lowest gear
The inner ring on the 11-25's biggest cog.
30 : 52
30T × 52T · climber's ring
MTB 30T · 10-52, lowest gear
Narrow-wide on SRAM's 94 × 4, in the cassette's lowest gear.
32 : 52
34 : 52
15 : 43
KLR650 · 15/43 steel
15/43 · 520
The KLR650's stock gearing on 520 chain: a 43T steel rear with six broad spokes and big rounded windows, on Kawasaki's 520 street pattern (6 × 10.5 mm on 104, 80 mm centre).
13 : 49
YZ250F · 13/49 offset spokes
13/49 · 520
Short motocross gearing: a 49T aluminium rear with six tapered spokes, each rim end turned 7° round of its hub end, on the Japanese motocross pattern (6 × 8.5 mm on 150, 125 mm centre).
13 : 48
KTM 350 EXC-F · 13/48
13/48 · 520
Enduro gearing: a 48T aluminium rear with six spokes tapering from 22 mm at the hub to 14 mm at the rim, on KTM's pattern (6 × 8.5 mm on 150, 125 mm centre).
15 : 45
ZX-6R · 15/45 swept
15/45 · 525
Track gearing two teeth shorter than stock, on 525 chain: a 45T aluminium rear with six swept spokes, on the ZX-6R's pattern (6 × 8.5 mm on 100).
13 : 51
KX450 · 13/51 mud
13/51 · 520
Mud-race gearing: a 51T steel rear with a notch at the bottom of every tooth gap to shed packed mud, and six wide spokes, on the Japanese motocross pattern (6 × 8.5 mm on 150, 125 mm centre).
15 : 47
R6 · 15/47 lattice
15/47 · 520
A 520 conversion for an R6 on Marchesini wheels: a 47T aluminium rear whose ten forked spokes cross into a lattice, on Marchesini's five-bolt pattern (5 × 10 mm on 100, 76 mm centre).
13 : 26
13/26 · ANSI 35
Industrial ANSI 35 · 13/26
Stock-style: Type B hubs, keyed bores, two set screws each.
15 : 45
15/45 · ANSI 40, ISO 14 splines
Industrial ANSI 40 · 15/45, ISO 14 splines
A 3 : 1 conveyor reduction on straight-sided splined shafts, each retaining ring flush in a counterbore.
17 : 34
17/34 · ANSI 50-2 duplex, ISO 4156 splines
Industrial ANSI 50-2 duplex · 17/34, ISO 4156 splines
Two rows of teeth for two-strand ⅝" chain, on involute splined shafts; each ring sits on the face over a splined washer, no counterbore.
19 : 57
19/57 · ANSI 60, ISO 14 splines
Industrial ANSI 60 · 19/57, ISO 14 splines
A 3 : 1 drive with a cast-style 57T wheel (a 22 mm deep rim, six 36 mm spokes) on straight-sided splined shafts, rings flush in counterbores on both faces.
21 : 42
21/42 · ANSI 80-3 triplex
Industrial ANSI 80-3 triplex · 21/42
Three rows of teeth for three-strand 1" chain.
17 : 38
17/38 · ISO 08B, ISO 4156 splines
Industrial ISO 08B · 17/38, ISO 4156 splines
The European ½" chain on involute splined shafts, rings on both faces with no counterbore.
Designing is free; the STL, STEP, DXF and SVG files download from the app for tokens. Strength figures are the Sprocket Designer's plane-stress check of each sprocket in the material it names.